need help with my fuzz face!!!

[morthek]

I done this fx pedal just like is said here ( http://www33.brinkster.com/mkzstompbox/esquemas.asp?escolha=fuzzfacenpn ) . this is a NPN trasistors Fuzz Face , it is almost good , the volume level is ok, the true bypass is ok, but the fuzz pot is not. it only work if the fuzz is turned on max position , if doesn´t no sound is presented. (and when is almost at max position a very distorted sound that goes alway very fast is presented)

can anyone help me?  sorry for the bad english
Thanks

[petemoore]

I use trimpot on Q2's collector for biasing.
 manythings like transistor orientation and stuff before debugging and tuning can occur.
 Sounds like if not a miswire or transistor pinout prob it is probably biasing.
 If you have a meter take readings between ground and each of Q1 and Q2's pins [the collector emitter and base readings]

[morthek]

forgot to tell. i have mounted a log pot in the of the linear pot that the schema said .... it is not the problem, is it?

[javacody]

Shouldn't be, you just need to get those transistors biased properly.  Do what petemoore suggested, and I bet you'll be up and running in no time.

[morthek]

i don´t know if i have done it right but here is the values:

Q1:   E: 0 (the meter dont even move)
       B: 35
       C: 145
Q2:   E: 105
       B: 145
       C: 155

i´ve used a analog metter so i dont know i if did it right, i´ve select "DC V 2.5" and the scale could be 5 , 1 or 0.2 .. so where is 35 it possible be 7 or even 1.4

[morthek]

any clue?

[petemoore]

Of trying to explain how to read an analog meter...[tricky at best..]
 Ill suggest this as a way to get by in this case [ and others] without having to get the DMM
 Take two equal value resistors and form a voltage divider [say two 10k  [or two 100k...] series them, connect them across the battery you're using, then test the Voltage between one of the battery contacts and the connection of the two resistors [should read very close to half of what the battery's voltage is]...then whatever you get on the meter measuring between Q2's collector and ckt ground should look very close to 1/2 of your battery:about 4.5v, or half of the battery voltage...

[morthek]

what hapens if the middle wire of the fuzz put isnt working? there should be no sound at all?

[petemoore]

The only times I've noticed FF's actually work is when everything is just as it should be accroding to the schematic [or very close]
 I can't stress enough how great the reads are aroundjust a few clicks [one] close to here...they do a better job of explaining thiss cktss FF than I can draft easily or at all...I am daunted by the amount of usable and complex [sometimes complex to the point of skimreading parts of it].
  I don't want to recommend just one site [inappropriate] there are so manyinteresting  'takes' on this thing.
  I would say for a first one that will work great [knkwood] use a schematic that looks like you can understand and the literature that accompaies it
  Basically understanding everything about a FF helps to build a FF, or any other ckt.
  Oh DMM... these FF's can be cruel however I did manage to get one going with a voltmeter....

[morthek]

Ok. now i got an DMM.. i have mettered the battery and it showed 9.3( shoul be 9?)
here is the readings:
Q1: E - 0
     B - 0,61
     C - 1,42
Q2: E - 0,78
     B - 1,42
     C - 1,71

its ok?

[petemoore]

at around 1/2 V of battery...
 try the articlees

[Gary]

morthek,

Reduce the value of the resistor going from V+ to the second transistor's collector.  You want to have about 4.5V on the second transistor's collector, if you are using a 9V battery.  Keep trying different values until you get as close to 4.5V as possible.  If you have an 8k2 resistor there, try a 5k6 or 6k2.  That should get you close.  As I said before, adjust until you get as close to 4.5V as you can when using a 9V battery.

[morthek]

i finnaly understand what was wrong, sorry about the silly questions, but i am very novice in electronics ,but i wont give up